Partial internal condenser

ABSTRACT

In the preferred form of this sheet metal refrigerator cabinet, an inturned front flange extending at right angles to the top and sidewalls has an inturned U-shaped stiffening fold which snugly receives a loop of refrigerant tubing located in the refrigerant circuit between the condenser and the evaporator. This construction not only stiffens the front door opening of the cabinet but also provides efficient heat transfer from the warm refrigerant tubing to the U-shaped fold to prevent condensation of atmospheric moisture around the door opening.

United States Patent Louis D. Benasutti Fairbom, Ohio 7 859,780

Sept. 22, 1969 Mar. 23, 1971 General Motors Corporation Detroit, Mich.

inventor Appl. No. Filed Patented Assignee PARTIAL INTERNAL CONDENSER 6 Claims, 6 Drawing Figs.

u.s. Cl 62/277, Y I 62/81 1111.01 r250 47/00 Field of Search 62/277, 181

References Cited UNITED STATES PATENTS 11/1938 Newill 62/277 w13,s72,0s1

2238,51 l 4/1941 Thaxter 62/275 2,476,906 7/ 1949 Philipp 62/277 2,647,374 8/1953 Stoner 62/275 3,157,306 1 1/1964 Courson 62/277 Primary Examiner-William .l. Wye Atlorneys-W. E. Finken, John C. Evans and Carl A. Stickel ABSTRACT: In the preferred form of this sheet metal refrigerator cabinet, an inturned front flange extending at right angles to the top and sidewalls has an inturned U-shaped stiffening fold which snugly receives a loop of refrigerant tubing located in the refrigerant circuit between the condenser and the evaporator. This construction not only stiffens the front door opening of the cabinet but also provides efficient heat transfer from the warm refrigerant tubing to the U- shaped fold to prevent condensation of atmospheric moisture around the door opening.

n v All /Z' v INVENTOR.

BY 00214 .0 fimasa/iz' M4. M4

ATTORNEY PARTIAL INTERNAL CONDENSER This invention pertains to a refrigerator cabinet construction provided with an arrangement for preventing condensation on its external walls adjacent the door opening. it is an object of this invention to provide an inexpensive efficiently insulated refrigerator cabinet with an inexpensive efficient heat transfer and reinforcing arrangement for using the heat of condensation of the refrigerant to prevent condensation of moisture adjacent the front door opening of the cabinet which also serves to reinforce the edges of the front door opening.

It is another object of this invention to provide an inexpensive reinforcing double inward flange arrangement at the front of a refrigerator cabinet shell with a loop of refrigerant tubing efficiently interfttted between such flanges to provide efficient metal to metal contact and heat transfer between the tubing and the adjacent portions of said flanges of said outer shell in which the tubing reinforces the double flange.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings, wherein preferred embodiments of the present invention are clearly shown.

In the drawings: i

FIG. 1 is a front view of an insulated refrigerator cabinet;

FIG. 2 is a side sectional view of the refrigerator cabinet shown in FIG. I;

FIG. 3 is a fragmentary horizontal sectional view showing one portion of the flange, bracket and tubing interfitting arrangement taken along the line 3-3 of .FIG. 1;

FIG. 4 is a fragmentary vertical sectional view takenalong the line 4-4 of FIG. 1 showing another portion of the flange and tubing heating arrangement; 7

FIG. 5 is a fragmentary vertical sectional view taken along the line 5-5 of FIG. I showing the bottom flange arrangement; and

FIG. 6 is a fragmentary horizontal sectional view taken along the line 6-6 of FIG. I showing the arrangement by which the refrigerant tubing and electric wiring enter through the rear wall of the refrigerated cabinet.

Referring now to the drawings and more particularly to FIGS. I and 2, there is shown an insulated refrigerator cabinet 10 having a continuous outer sheet metal wall extending up the sides 11 and 12 and across the top 13 to form the outer top and sidewalls of the cabinet. These walls are provided with an inturned flange 14 at the rear which is connected to the flanges of the sheet metal rear panel I5. At the bottom. the sidewalls are provided with reinforcing supporting the feet 16. Within the cabinet there is provided a bottom wall 5 having a low front portion 6 and a higher rear portion 7. This is fastened to the sidewalls 11 and 12, to rear wall 15 and the front lower cross member 9. j

The sidewalls ll and I2 and the top wall 13 are reinforced at the front with an inwardly turned flange I01 extending inwardly substantially at right angles to the side and top walls around the door opening. Preferably this flange 101 is rounded at the corner and formed of a double thickness of metal by being folded back sharply as illustrated in FIGS. 3 and 4. This inturned portion is substantially in the form of a U shape with the open side turned inwardly with an inner leg or flange 103 substantially parallel to the flange 101. This is formed of thin resilient sheet metal so that the flange 103 is relatively springy. The corner 105 formed between the flange 101 and the top and sidewalls l3 and 11-12 preferably is rounded substantially about the center of the rounded portion of the Ushape formed by the flange 101 and the flange 103. The rounded portion of the U is formed in substantially a semicircular pattern with a diameter substantially equal to the space between the flange 103 and the-flange 101. The corner 105 has a radius slightly larger than the semicircular portion of the U-shape. This configuration reinforces the front of the walls and the door opening and makes adjacent areas substantially rigid laterally.

According to my invention there is lodged tightly within this U-shape double flange arrangement, a loop of refrigerant tubing 107 having an outer diameter substantially equal to the distance between the flanges 101 and 103. This loop of refrigerant tubing has one end connected to the outlet of the refrigerant condenser I09 and the other end connected to a filter 111 which connects through a capillary supply tube 113 extending through the suction conduit II5 to a refrigerant evaporator 32 mounted inside the cabinet. The sealed motor compressor unit is connected between the suction conduit 115 and the condenser 109. This loop 107 throughout its greater portion is lodged as close as possible to the comer 105 to provide 180 of metal-to-metal contact but it may be provided with necked in portions 117 on both sides to provide added flexibility and also for convenience in attaching the brackets 71 as illustrated in FIG. 3. Thus, the tubing 107 fits snugly over the greater portion of its length adjacent and within the comer I05 and firmly contacts the semicircular portion of the U-shaped flange arrangement I01, 103 along the top and sides of the door opening to provide excellent heat transfer with the outer walls as well as effective structural reinforcement. p Also inserted into the U-shaped flange arrangement between the flanges I01 and I03 is a resilient foam plastic strip 119 such as foamed open cell polyethylene which initially is of uniform thickness and extends slightly more than the distance between the edge of the flange I03 and the tubing 107. This strip 119 extends across the top wall 13 and down the sides 11 and 12 substantially to the bottom of the door opening. It may be provided with an adhesive on the surface contacting the flange 103 for adhering to it.

The interior of the cabinet is provided by a box-shaped inner liner 17 preferably formed out of a suitable sheet plastic such as acrylic butadiene styrene copolymer having an out turned flange 121 at the front which snaps into place between the legs of the U-shaped tubular flange arrangement provided by the flanges IOII03 and compresses the adjacent portion of the resilient foam plastic strip 119 of polyethylene open cell foam to seal the front of the cabinet. Preferably the front outer portion of this liner I7 is covered by a thin sheet I23 of polyethylene which preferably is provided with an adhesive so that it adheres to the outer surface of the liner I7 entirely around the front thereof adjacent the flange 121. The flange I21 and the resilient polyethylene foam strip 119 provide a seal. between the flanges I01 and 103 for preventing the escape of the foam insulation material during its introduction while permitting the escape of trapped air and gases from the space between the inner walls provided by the inner liner I7 and the outer walls of the cabinet designated by the reference characters ll, l2, l3 and 5 and 15. Preferably this insulation space is filled with polyurethane foam I25 containing an insulating gas which will be retained within the cells thereof. This foam insulation reinforces the inner and outer walls of the cabinet and makes it substantially rigid. The polyethylene sheet 123 prevents adherenceof the foam insulation 125 to the liner l7 and thereby minimizes the objectionable effects of differences in thermal expansion and decreases the possibility of cracking.

The brackets 71 extend through openings in the flange I03 and are fastened by the screws 72 to the flange I01. By the screws 132 they support a front metal cross member I31 extending between them. This front cross member 131 supports a metal or plastic trim strip 133 and also the front edge of a laterally extending sheet metal wall 22 having an upturned flange at the rear provided with threaded fastening means extending through the liner 17 into a pair of supports 93 within the insulation space between the liner 17 and the rear wall 15 to which they are attached by threaded fastening means. These supports may be made of fiber glass and a high-temperature thermoset plastic such as a polyester or phenolic thermosetting resin. This wall 22 supports thermal insulating means as well as an evaporator drain pan 21 which supports the evaporator 24. The pan 21 also supports a fan motor I47 and a fan 149 at the rear which draws air from the upper compartment 143 through the apertures 151 in the support 153 and from the lower compartment 145 through the apertures 155 in the sheet metal wall 22 through the evaporator and discharges the air through the ducts 157,159 back to these compartments. The capillary tube 113 and the suction line 115 (one within the other) extend through the double grommet 624 (see FIG. 6) in the rear wall and connect to the evaporator 24.

Across the bottom of the inner liner 17, the flange 121 overlaps a polyethylene seal 135 which is provided with an adhesive to adhere to an offset flange portion 137 at the front 9 of the bottom member 5. This overlapping arrangement prevents any liquid spilled within the liner from reaching the insulation 125.

The necked in portions 117 of the loop of refrigerant tubing 107 rest between the flanges 101 and 103 against the adjacent portions of the brackets 71 so as to provide sufficient heat transfer between the portions 117 and the brackets 71 as well as the cross member 131 and its trim strip 133 to diminish or prevent condensation of this mullion strip which extends between the upper front door 139 and the lower front door 141 of the cabinet which close the upper compartment 143 and the lower compartment 145. Thus, by placing the loop of refrigeration tubing 107 in between the legs 101,103 of the reinforcing double flange and by making the tubing contact the brackets 71, the problem of condensation is eliminated in an economical manner. In addition, this heat transfer serves to further cool the liquid refrigerant before it enters the capillary restrictor tube 113 on its way to the evaporator 24 to improve the thermal efficiency of the refrigerating system. It also makes the U-shaped reinforcing flange 101,103 more rigid. The lower compartment 145 is provided with a plurality of cantilever shelves 160 provided with hooks at the rear which are adapted to hook into a vertical series of apertures in the upright rack bars 162 on the rear wall of the compartment. These racks are each supported from upper and lower supports and 153 extending between the inner liner 17 and the rear wall 15 and fastened to the rear wall by threaded fastening means. These supports 151 and 153 are preferably made of glass fibers and a high-temperature thermoset plastic such as a polyester or phenolic thermosetting resin.

While the embodiments of the invention as herein disclosed constitute preferred forms, it is to be understood that other forms might be adopted.

lclaim:

1. A refrigerator cabinet construction provided with a front door opening including an outer sheet metal shell comprising top and sidewalls provided with an integral intumed flange at the front turned in substantially at a right angle to the side and top walls, said intumed flange along the greater portion of said top and sidewalls being provided with an additional intumed flange of thin resilient sheet metal substantially parallel to it and spaced rearwardly a substantially uniform distance from said integral intumed flange, wherein the improvement comprises a loop of tubing adapted to contain a warm fluid having an outer diameter substantially equal to said uniform distance extending longitudinally of said flanges between and in contact with said flanges to provide heat transfer between said tubing and said flanges.

2. A refrigerator cabinet construction provided with a front door opening including an outer sheet metal shell comprising top and sidewalls provided with an integral intumed flange at the front turned in substantially at a right angle to the side and top walls, said intumed flange along the greater portion of said top and sidewalls being provided with an additional intumed flange of thin resilient sheet metal substantially parallel to it and spaced rearwardly a substantially uniform distance from said integral intumed flange, wherein the improvement comprises a loop of tubing adapted to contain a warm fluid having an outer diameter substantially equal to said uniform distance extending longitudinally of said flanges between and in contact with said flanges to provide heat transfer between said tubing and said flanges, inner top and sidewalls within said outer sheet metal shell spaced from said top and sidewalls of said shell, said inner walls having out-turned top and side flanges of a nonmetallic material extending between said intumed flanges of said outer shell, a strip of a resilient foam material extending longitudinally of said flanges between said out-turned flange of said inner wall and said additional flange along the inner periphery of said loop of tubing, and a more rigid foam insulating material located between the top and sidewalls of said shell and the top and sidewalls of said inner walls.

3. A refrigerator cabinet as defined in claim 2 in which a thin plastic sheet which is substantially nonadhcrcnt to said more rigid foam insulation material, extends around and in contact with the outer surface of said inner walls adjacent and rearwardly of said out-turned flange to reduce the area of bonding between said more rigid foam insulation material and said inner walls.

4. A refrigerator cabinet construction wherein the improvement comprises an outer sheet metal shell comprising top and sidewalls provided with an integral intumed flange turned substantially at a right angle to the top and sidewalls, said integral intumed flange having an integral rearwardly folded portion with a sharp rearward bend and extending along its inner side provided with a rearward bend substantially in the form of a half circle and with an additional integral intumed flange, said flange extending from said half circular bend inwardly substantially parallel to said first inturned flange and spaced from said first intumed flange a predetermined distance, and a loop of tubing adapted to contain a warm fluid having an outer diameter substantially equal to said uniform distance and said half circular bend, said loop extending longitudinally of said flanges between and in contact with said flanges and said half circular bend.

5. A refrigerator cabinet construction provided with a front door opening including an outer sheet metal shell comprising top and sidewalls provided with an integral intumed flange at the front turned in substantially at a right angle to the side and top walls, said intumed flange along the greater portion of said top and sidewalls being provided with an additional inturned flange of thin resilient sheet metal substantially parallel to it and spaced rearwardly a substantially uniform distance from said integral intumed flange, wherein the improvement comprises a loop of tubing having an outer diameter substantially equal to said uniform distance extending longitudinally of said flanges between and in contact with said flanges to provide heat transfer between said tubing and said flanges, said shell having a bottom wall lower in front and higher in the rear provided with aperture means between said lower and higher portions, said inner walls having a bottom wall spaced above the bottom wall of said shell, said loop of tubing having lower portions extending rearwardly between the front portions of said bottom walls through said aperture means, and a refrigerant liquefying means connected to one portion of said loop of tubing outside of said shell.

6. A refrigerator cabinet construction provided with a front door opening including an outer sheet metal shell comprising top and sidewalls provided with an integral intumed flange at the front turned in substantially at a right angle to the top and sidewalls, said intumed flange along the greater portion of said top and sidewalls being provided with an additional inturned flange of resilient sheet metal substantially parallel to it and spaced rearwardly a substantially uniform distance from said integral intumed flange, a mullion construction extending between said sidewalls to divide the front opening, metal bracket means extending from said intumed flange to said mullion construction, wherein the improvement comprises a loop of tubing adapted to contain a warm fluid having an outer diameter substantially equal to said uniform distance extending longitudinally of said flanges between and in contact with said flanges and said metal brackets to provide heat transfer between said tubing and said flanges and said metal brackets for preventing condensation upon said outer shell and said mullion construction. 

1. A refrigerator cabinet construction provided with a front door opening including an outer sheet metal shell comprising top and sidewalls provided with an integral inturned flange at the front turned in substantially at a right angle to the side and top walls, said inturned flange along the greater portion of said top and sidewalls being provided with an additional inturned flange of thin resilient sheet metal substantially parallel to it and spaced rearwardly a substantially uniform distance from said integral inturned flange, wherein the improvement comprises a loop of tubing adapted to contain a warm fluid having an outer diameter substantially equal to said uniform distance extending longitudinally of said flanges between and in contact with said flanges to provide heat transfer between said tubing and said flanges.
 2. A refrigerator cabinet construction provided with a front door opening including an outer sheet metal shell comprising top and sidewalls provided with an integral inturned flange at the front turned in substantially at a right angle to the side and top walls, said inturned flange along the greater portion of said top and sidewalls being provided with an additional inturned flange of thin resilient sheet metal substantially parallel to it and spaced rearwardly a substantially uniform distance from said integral inturned flange, wherein the improvement comprises a loop of tubing adapted to contain a warm fluid having an outer diameter substantially equal to said uniform distance extending longitudinally of said flanges between and in contact with said flanges to provide heat transfer between said tubing and said flanges, inner top and sidewalls within said outer sheet metal shell spaced from said top and sidewalls of said shell, said inner walls having out-turned top and side flanges of a nonmetallic material extending between said inturned flanges of said outer shell, a strip of a resilient foam material extending longitudinally of said flanges between said out-turned flange of said inner wall and said additional flange along the inner periphery of said loop of tubing, and a more rigid foam insulating material located between the top and sidewalls of said shell and the top and sidewalls of said inner walls.
 3. A refrigerator cabinet as defined in claim 2 in which a thin plastic sheet which is substantially nonadherent to said more rigid foam insulation material, extends around and in contact with the outer surface of said inner walls adjacent and rearwardly of said out-turned flange to reduce the area of bonding between said more rigid foam insulation material and said inner walls.
 4. A refrigerator cabinet construction wherein the improvement comprises an outer sheet metal shell comprising top and sidewalls provided with an integral inturned flange turned substantially at a right angle to the top and sidewalls, said integral inturned flange having an integral rearwardly folded portion with a sharp rearward bend and extending along its inner side provided with a rearward bend substantially in the form of a half circle and with an additional integral inturned flange, said flange extending from said half circular bend inwardly substantially parallel to said first inturned flange and spaced from said first inturned flange a predetermined distance, and a loop of tubing adapted to contain a warm fluid having an outer diameter substantially equal to said uniform distance and said half circular bend, said loop extending longitudinally of said flanges between and in contact with said flanges and said half circular bend.
 5. A refrigerator cabinet construction provided with a front door opening including an outer sheet metal shell comprising top and sidewalls provided with an integral inturned flange at the front turned in substantially at a right angle to the side and top walls, said inturned flange along the greater portion of said top and sidewalls being provided with an additional inturned flange of thin resilient sheet Metal substantially parallel to it and spaced rearwardly a substantially uniform distance from said integral inturned flange, wherein the improvement comprises a loop of tubing having an outer diameter substantially equal to said uniform distance extending longitudinally of said flanges between and in contact with said flanges to provide heat transfer between said tubing and said flanges, said shell having a bottom wall lower in front and higher in the rear provided with aperture means between said lower and higher portions, said inner walls having a bottom wall spaced above the bottom wall of said shell, said loop of tubing having lower portions extending rearwardly between the front portions of said bottom walls through said aperture means, and a refrigerant liquefying means connected to one portion of said loop of tubing outside of said shell.
 6. A refrigerator cabinet construction provided with a front door opening including an outer sheet metal shell comprising top and sidewalls provided with an integral inturned flange at the front turned in substantially at a right angle to the top and sidewalls, said inturned flange along the greater portion of said top and sidewalls being provided with an additional inturned flange of resilient sheet metal substantially parallel to it and spaced rearwardly a substantially uniform distance from said integral inturned flange, a mullion construction extending between said sidewalls to divide the front opening, metal bracket means extending from said inturned flange to said mullion construction, wherein the improvement comprises a loop of tubing adapted to contain a warm fluid having an outer diameter substantially equal to said uniform distance extending longitudinally of said flanges between and in contact with said flanges and said metal brackets to provide heat transfer between said tubing and said flanges and said metal brackets for preventing condensation upon said outer shell and said mullion construction. 